Probe nose training cartridge

ABSTRACT

The bullet for a training cartridge has a thin probe extending therefrom to reduce its maximum range. The training cartridge provides realistic trajectory, sound, recoil and sighting accuracy and produces identifiable target penetration with reduced risk of richochet and to create the same cartridge profile as a conventional round but with limited range suitable to training purposes. The thin, elongated probe has a blunted nose and joins the main body of the bullet on a tapered surface.

GOVERNMENT INTEREST

The invention described herein was made in the course of or underContract No. DAAK10-82-C-0236 thereunder with the Government and may bemanufactured, used and licensed by or for the Government forGovernmental purposes without the payment to us of any royaltiesthereon.

BACKGROUND OF THE INVENTION

This invention relates to a bullet structure for a conventionalcartridge, and more specifically relates to a novel bullet structurewhich has a limited range suitable for training purposes, but whichotherwise reproduces the other important bullet characteristicsnecessary for training purposes.

Conventional ammunition, particularly machine gun ammunition, isexpensive and has a very long range. For example, conventional caliber0.50 ammunition used in the M2 machine gun with a bullet which complieswith the M33 cartridge envelope has a maximum range o approximately6,700 meters. Such bullets have sufficiently high kinetic energy that,even after interception by a target on a target range, they will carryfor extensive distances and will be subject to considerable ricochet. Asa result, machine gun training for military personnel is restricted to afew military facilities which have sufficient range.

There exist various types of short-range training ammunition. These,however, do not provide training at realistic target ranges and requirethe use of a special adapter or recoil amplifier which will cause aconventional weapon to cycle properly, and to exhibit realisticcharacteristics which are experienced at normal target engagementdistances.

BRIEF DESCRIPTION OF THE INVENTION

In accordance with the present invention, a novel bullet having anextending probe-shaped nose is provided which can be assembled with aconventional cartridge case. The extending probe-shaped nose has ablunted end and joins the main body of the bullet at a sharply taperedsurface. The bullet will then have a limited maximum range of about4,000 meters while still providing realistic training characteristicssuch as realistic sighting accuracy, trajectory, sound and recoil fortargets at normal engagement ranges, such as 800 to 1,000 meters.

Thus, maximum range is reduced by about 40% as compared to conventionalammunition. The bullet also complies with the M33 cartridge envelope. Ingeneral, the bullet has drag and inertial characteristics which closelymatch the ballistic characteristics of conventional caliber 0.50ammunition to a range of 800 to 1,000 meters but has a maximum range ofonly about 4,000 meters.

The projectile or bullet has sufficient kinetic energy when fired tomark standard military targets. Target penetration also creates a highprobability of bending the probe nose to reduce stability and increasedrag for further range reduction. The shape of the bullet with itsprobe-shaped nose and flat face also helps reduce ricochet.

Other features and advantages of the present invention will becomeapparent from the following description of the invention which refers tothe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of the novel bullet of the presentinvention.

FIG. 2 is an end view of the probe end of the bullet of FIG. 1.

FIG. 3 is a cross-sectional view of a portion of the major body portionof the bullet of FIG. 1 in the circled area labeled "A" in FIG. 1.

FIG. 4 is a side elevation view of a training cartridge containing thenovel bullet of FIGS. 1, 2 and 3.

FIG. 5 is an end view of the left-hand end of the cartridge of FIG. 4.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring first to FIGS. 1, 2 and 3, there is shown therein the novelprobe nose training bullet 10 which is a monolithic structure preferablymade of an annealed leaded steel to provide good machinability orformability. The use of the softer steel will also reduce barrel wear.

The bullet 10 consists of a generally cylindrical body section 11 whichextends from a cartridge end 12 suitably tapered for mounting into astandard brass cartridge case 13 as shown in FIGS. 4 and 5. Cartridgecase 13 may have the dimensions and structure used for conventionalcaliber 0.50 cartridges.

The generally cylindrical body section 11 of bullet 10 has a firsttapered surface 14 which forms a relatively shallow angle relative tothe axis of the bullet 10.

In a typical embodiment of the invention, region 11 will have a maximumdiameter of about 0.5 inch and will extend for a length of approximately1.25 inches. The bullet then has a sharply tapered surface 15 extendingover a length of about 3/8 inch and reduces to a diameter of about 0.125inch. A probe section 16 then extends from the right-hand end of taper15 for a length of approximately 1/2 inch. The actual length of theprobe 16 and its diameter can be adjusted depending upon the specificrange characteristics which are desired for the device. The end surface17 of probe 16 is preferably blunted as by having a relatively largediameter as shown in FIG. 1.

FIG. 4 shows the bullet of FIGS. 1, 2 and 3 assembled with aconventional cartridge 13. The cartridge 13 will have a standard primer18 and a standard propellant can be used for the cartridge. The bullet10 and cartridge 13 are assembled using standard assembly techniques.

The novel bullet of the present invention is well adapted to machine guntraining under limited range conditions. It will be apparent that thenovel bullet of the invention is applicable to cartridges for otherapplications.

The interior ballistics of the round are such that it provides realisticnoise, flash, recoil and firing rate without need for special adaptersor recoil amplifiers. The projectile has drag and inertialcharacteristics which provide a close ballistic match to conventionalcaliber 0.50 ammunition to a range of about 800 to 1,000 meters but ithas a maximum range of only about 4,000 meters. This provides realisticsighting practice for the gunner at target ranges normally encounteredbut reduces maximum bullet travel significantly from the maximum rangeof approximately 6,700 meters for conventional caliber 0.50 ammunition.The shape of the bullet with the probe nose 16 and flat face also helpsreduce ricochet.

The probe 16 accomplishes two objectives: It provides the necessaryoverall length to ensure automatic bullet feed, and has a relativelyblunt nose to increase the bullet drag. The shape of the nose 16 can bevaried as desired and the length of the probe 16 can be varied both toadjust drag characteristics and gun feed characteristics as necessaryfor desired performance.

The bullet 10 has a weight of 480 grains and a muzzle velocity of 3,430feet per second. Any desired small arms propellant can be used toproduce the required interior ballistics within the constraints of thestandard military brass cartridge case 13.

The foregoing disclosure and drawings are merely illustrative of theprinciples of this invention and are not to be interpreted in a limitingsense. We wish it to be understood that we do not desire to be limitedto the exact details of construction shown and described because obviousmodifications will occur to a person skilled in the art.

What is claimed is:
 1. A bullet for a training cartridge; said bullethaving a generally cylindrical body section, one end of which isreceivable into a cartridge case; said cylindrical body section having afirst diameter at a given axial position and having an elongated probesection extending from the opposite end of said cylindrical bodysection; said elongated probe section being coaxial with saidcylindrical body section; said elongated probe section having a lateralwidth which is less than said first diameter and a length which is atleast about 25% of the total length of said bullet.
 2. The bullet ofclaim 1 wherein said probe section is cylindrical in cross-section; thediameter of said probe section being less than about 1/2 of said firstdiameter.
 3. The bullet of claim 1 wherein the free end of said probesection has a blunt nose to increase drag and reduce range.
 4. Thebullet of claim 2 wherein the free end of said probe section has a bluntnose to increase drag and reduce range.
 5. The bullet of claim 4 whereinsaid blunt nose has a generally arcuate shape.
 6. The bullet of claim 1wherein said cylindrical body section has a first tapered shapeextending axially for a first length from a diameter at an axialposition adjacent said one end to said first diameter; said firstdiameter being smaller than said large diameter; said cylindrical bodysection having a second tapered shape of relatively short lengthcompared to said first length and which extends from said first diameterto the beginning of said probe section.
 7. The bullet of claim 6 whereinsaid probe section is cylindrical in cross-section; the diameter of saidprobe section being less than about 1/2 of said first diameter.
 8. Thebullet of claim 7 wherein the free end of said probe section has a bluntnose to increase drag and reduce range.
 9. The bullet of claim 8 whereinsaid blunt nose has a generally arcuate shape.
 10. The bullet of claim 1wherein said bullet consists of an annealed leaded steel.
 11. The bulletof claim 2 wherein said bullet consists of an annealed leaded steel. 12.The bullet of claim 5 wherein said bullet consists of an annealed leadedsteel
 13. The bullet of claim 6 wherein said bullet consists of anannealed leaded steel.
 14. The bullet of claim 9 wherein said bulletconsists of an annealed leaded steel.